Novo Nordisk CEO Mike Doustdar on Wednesday defended the drugmaker’s decision to sue rival Eli Lilly over its weight-loss drug advertising.
“I am a big fan of competition. I think competition has to be fierce, but I also think competition has to be fair,” Doustdar said on CNBC’s “Mad Money.” “I believe that patients deserve to know the full truth together with their physicians before they make a choice of what product to take.”
Last month, Novo Nordisk filed a lawsuit, alleging that Lilly’s advertising for its blockbuster injectable GLP-1 drugs misleads consumers about their efficacy relative to Novo’s rival treatments. In a statement at the time, Lilly said it stands “firmly behind our advertising.”
In its ads, Lilly cites a head-to-head trial it conducted of its obesity drug Zepbound versus Novo Nordisk’s rival treatment Wegovy. The results appeared in The New England Journal of Medicine in May 2025. The trial data showed that the maximum tolerated dose of 10 mg or 15 mg of Zepbound over 72 weeks yielded average weight loss of 20.2%, or around 50 pounds, compared to 13.7%, or roughly 33 pounds, for the then-maximum tolerated dose of 1.7 mg or 2.4 mg for Wegovy.
Doustdar argued Lilly’s comparisons do not give consumers the full picture because they rely on an older, lower-dose version of Novo’s Wegovy rather than the company’s newer high-dose 7.2 mg offering, which was approved by the Food and Drug Administration back in March. Novo said it conducted a study of 7.2 mg Wegovy and saw average weight loss over 72 weeks of about 19%, or 47 pounds — much closer to the max-dose Zepbound in the previous study.
“We believe that the advertisements that they have been doing, while truthful, is not the complete picture,” Doustdar said. “It’s built on older generations of these products and old doses,” he added. “People need to know that there is a more advanced version of Wegovy in the market with a different profile, and then they can make their choice and decide which product is the best.”
When asked for comment, an Eli Lilly spokesperson said, “We’re glad to see Novo Nordisk’s own CEO confirm what we’ve said all along: Lilly’s advertising is truthful. As for the suggestion that Wegovy HD is on par with Zepbound, that comparison isn’t supported by any head-to-head clinical trial. Novo knows this and that is why you have never before heard them say this in their paid consumer advertising. The reality is that Zepbound is the most prescribed obesity medicine in the U.S. Lilly stands behind its science and the only head-to-head trials comparing these two medicines.”
The legal fight comes as competition between Novo Nordisk and Eli Lilly intensifies across the booming GLP-1 market. Doustdar acknowledged Lilly has gained market share, particularly in injectable weight-loss drugs. Since the suit was filed, Novo shares have fallen 6%, while Eli Lilly has climbed nearly 4%.
“There is no secret that Lilly has been quite successful, actually, in having volume uptake and market share uptake above and beyond Novo” in injectables, Doustdar said.
At the same time, Doustdar touted the company’s new Wegovy pill, which launched in early January following late December 2025 approval from the FDA. He said prescriptions in the U.S. have surpassed 5 million, claiming the Wegovy pill has been the “best product launch in the history of pharmaceuticals.”
Lilly has its own weight-loss pill, called Foundayo, which was approved by the FDA on April 1 and started shipping days later. The Wegovy pill has a head start, and that was evident in Lilly’s latest earnings report. While results were strong, Foundayo missed expectations as the company works to build up consumer awareness.
Lilly is a stock in Jim Cramer’s Charitable Trust, which is the portfolio used by the CNBC Investing Club.
